(04-29-2015 07:41 AM)Mark Douglas Wrote: Bilevel cpap is touted to increase compliance. If that be the case why wouldn't every cpap user want one? This concept is what prompted me to acquire such a machine out of the gate. If I find it causes complications due to markedly improved respiration it can be dumbed down until my body adjusts.

I will be looking forward to following in your wake.

Edited cause I slept really poorly and can't think yet this AM.

I have both the PRS1 760 BiPAP and a 560 Auto. I have done a lot of experimenting with the BiPAP and I'll be honest with you. I get significantly lower AHI and RERA with less pressure variance. I have been working with a pressure support of 5.0 for about a month and have had AHI ranging from less than 1.0 to over 3.0. Last night I used the auto again, and was right back to 0.6. Go figure.

I used the 560 last night and had a great night. While I've been trying to work with higher pressure support, statistically it is not my best treatment, however it is very comfortable and good enough. My best BiPAP prescription is EPAP min 10 cm, PS 2-4 (auto), IPAP max 18. That is both comfortable and works well.

On the 560, I generally run 11-14 auto A-Flex 1 and is close to results on BiPAP.

It is interesting to run the BiPAP with a lot of pressure support, and I can actually feel the machine kick in on a hypopnea or CA and add pressure for the inhale. Nevertheless, I consistently have higher AHI when I use that pressure support.

I think it's interesting that I can get better rest with the BiPAP in spite of higher AHI, and I think it comes down to a higher RERA being the difference, and the fact the apneas I have on BiPAP are mainly CA events that really are not of long enough duration to wake me.

The other take-away is that, there are so many different ways to get good treatment with a BiPAP unit. It takes a while to try the alternatives and see what works best.

(04-29-2015 04:48 PM)Sleeprider Wrote: I used the 560 last night and had a great night. While I've been trying to work with higher pressure support, statistically it is not my best treatment, however it is very comfortable and good enough. My best BiPAP prescription is EPAP min 10 cm, PS 2-4 (auto), IPAP max 18. That is both comfortable and works well.

On the 560, I generally run 11-14 auto A-Flex 1 and is close to results on BiPAP.

It is interesting to run the BiPAP with a lot of pressure support, and I can actually feel the machine kick in on a hypopnea or CA and add pressure for the inhale. Nevertheless, I consistently have higher AHI when I use that pressure support.

Hi Sleeprider,

Actually, neither of your machines will treat Central Apneas. Both will put out a Philips Respironics System One "pressure pulse" near the start of an apnea in order to determine whether it is central or obstructive, and if the apnea is central the machine will not change its pressure settings.

Membership in the Advisory Member group should not be understood as in any way implying medical expertise or qualification for advising Sleep Apnea patients concerning their treatment. The Advisory Member group provides advice and suggestions to Apnea Board administrators and staff on matters concerning Apnea Board operation and administrative policies - not on matters concerning treatment for Sleep Apnea. I think it is now too late to change the name of the group but I think Voting Member group would perhaps have been a more descriptive name for the group.

(04-30-2015 05:07 PM)Sleeprider Wrote: I think it's interesting that I can get better rest with the BiPAP in spite of higher AHI, and I think it comes down to a higher RERA being the difference, and the fact the apneas I have on BiPAP are mainly CA events that really are not of long enough duration to wake me.

The other take-away is that, there are so many different ways to get good treatment with a BiPAP unit. It takes a while to try the alternatives and see what works best.

Your RDI is about the same whether you use the Auto machine or the BiPAP Auto machine, but, as you have pointed, with BiPAP Auto your AHI is mostly CAs which happen to be short and apparently are not causing arousals and are not as disturbing to your sleep as RERAs are.

RERA events are actual arousals caused by partial obstruction of the airway and the needing to exert excessive effort, but the excessive effort had been successful enough in maintaining airflow that the reduction in airflow was too little for the event to be classified as an Hypopnea.

The higher the amount of PS, the higher the number of CAs you get, but the fewer RERA.

On the Auto machine, A-Flex settings of 1, 2 or 3 all add 2 cmH2O of pressure relief during exhalation, plus at least a small amount of additional pressure relief based on the rate of airflow. A setting of three adds the most pressure relief while we are actively exhaling. But a setting of 3 also reduces the IPAP pressure too early at the end of inhalation, while we are still trying to finish the last bit of our inhalation, as the rate of inhaling air is slowing down.

Membership in the Advisory Member group should not be understood as in any way implying medical expertise or qualification for advising Sleep Apnea patients concerning their treatment. The Advisory Member group provides advice and suggestions to Apnea Board administrators and staff on matters concerning Apnea Board operation and administrative policies - not on matters concerning treatment for Sleep Apnea. I think it is now too late to change the name of the group but I think Voting Member group would perhaps have been a more descriptive name for the group.

Thanks Vsheline for responding to this. I was away for a weekend motorcycle rally and had not looked in on the forum. Appreciate your insights. My treatment is just fine with either machine, but it is an interesting paradox that with the BiPAP I have somewhat higher AHI consisting of mostly CA that isn't treatable with pressuree, but low RERA, while the APAP produces consistently low AHI but higher RERA. I guess I can take my choice.

Assuming no ramp, you start out with an EPAP (exhale pressure) of 8.0. To get the IPAP (inhaling pressure) we add the PS of 9.0 to get 17.0. As you breathe the machine will raise and lower both the IPAP and the EPAP, but always keep them apart by 9.0. The highest your IPAP can go is 25.0, so at that time you'd have an EPAP of 16.0.

So IPAP ranges from 17.0 to 25.0.
EPAP ranges from 8.0 to 16.0.
PS is always fixed at 9.0, so IPAP minus EPAP is always 9.0.

PRS1 BiPAP's allow the PS to vary and they also have Bi-Flex which lowers the EPAP even further and changes the shape of the inspiratory portion of the pressure graph.

INFORMATION ON APNEA BOARD FORUMS OR ON APNEABOARD.COM SHOULD NOT BE CONSIDERED AS MEDICAL ADVICE. ALWAYS SEEK THE ADVICE OF A PHYSICIAN BEFORE SEEKING TREATMENT FOR MEDICAL CONDITIONS, INCLUDING SLEEP APNEA. INFORMATION POSTED ON THE APNEA BOARD WEB SITE AND FORUMS ARE PERSONAL OPINION ONLY AND NOT NECESSARILY A STATEMENT OF FACT.

INFORMATION ON APNEA BOARD FORUMS OR ON APNEABOARD.COM SHOULD NOT BE CONSIDERED AS MEDICAL ADVICE. ALWAYS SEEK THE ADVICE OF A PHYSICIAN BEFORE SEEKING TREATMENT FOR MEDICAL CONDITIONS, INCLUDING SLEEP APNEA. INFORMATION POSTED ON THE APNEA BOARD WEB SITE AND FORUMS ARE PERSONAL OPINION ONLY AND NOT NECESSARILY A STATEMENT OF FACT.